The suicide lead is not the only set Froslass uses. Froslass has a bulky set as well, and as Kokoloko stated earlier, there's a reason the bulky set is listed first on the analysis page. Froslass's Ghost-typing is actually quite useful on the bulky set as you can abuse Pain Split and not die after setting up spikes. Most good players would actually argue that bulky Froslass, although harder to use, is much more consistent when used properly.
If the bulky set is "listed first on the analysis page" for a reason, then why are all the suspect reasons based on the lead suicide set?
But your point about being hard to use is sort of my entire point of why Froslass doesn't deserve to be suspected. Yes, Froslass can be deadly in the right hands. It can set up lots and lots of hazards on players who aren't very experienced. However,
regardless of which set is better, the fact remains that Pain Split on Froslass is used less than Spikes (84%), Destiny Bond (77%), Ice Beam, Taunt, Shadow Ball, Thunder Wave, Thunderbolt, and Substitute. What I'm trying to say here is that Suicide Lead Froslass is overwhelmingly the majority of Frosslass used in the meta, and therefore it should only be considered for suspect based on that set. No matter how good the bulky Pain Split set might be, the fact that so few people use it makes it completely nontoxic to the metagame purely because it isn't used.
For the sake of fairness, I'm going to compare and contrast the various spikers in the tier based on their main hazard-laying set, because that's what we should be suspecting froslass for.
Pros:
+ Access to Destiny Bond
+ Access to fast Taunt/DBond, allows it to outspeed most nonscarf
+ Access to Thunder Wave
+ Moderately strong stab in Ice Beam and access to TundraBolt if coverage is desired over utility
+ Cursed Body hax
+ Ghost typing makes it immune to Fighting and Normal-Type attacks as well as most priority
+ Can not be frozen
Cons:
- Weakness to SR combined with extreme frailty makes it only useful very early-game
- 5 weaknesses
- Is very predictable
- Can easily be outpredicted by speed-boosting sweepers (DD Scrafty, Sub Sharpedo) and become fodder for a sweep
- Loses to faster Taunt or Prankster (Sableye, Tornadus)
- Loses to multihit moves like Rhyperior's Rock Blast
- Early death in most games makes it ineffective as a spinblocker
- Loses to VoltTurn + Scarfer
Pros:
+ Access to Destiny Bond
+ Access to Thunder Wave
+ Access to Taunt
+ Access to Spikes and Toxic Spikes
+ Access to Pain Split for reliable recovery
+ Decent speed and attack
+ Intimidate makes it a long-lasting spiker as well as an amazing physical wall
+ Access to Haze
+ Access to Explosion for pseudo-hazing
+ Optional dual stab options
+ 3 Weaknesses
+ Wide variety and use of utility moves makes it unpredictable
+ Useful as a lead and/or a mid-game player
+ Grounded Poison typing makes it able to absorb TSpikes
+ Immune to Toxic
Cons:
- Awful special bulk
- Poison typing makes it less effective of a physical wall when faced with Flygon/Krookodile
- Middling speed makes it lose out on some Destiny Bond KOs that Froslass gets
- Weak to Volt Switch
Pros:
+ Access to Toxic Spikes and/or Spikes
+ Access to strong stabs in Giga Drain, Leaf Storm, Sludge Bomb
+ Access to Sleep Powder
+ Access to reliable recovery with Synthesis / Rest + Natural Cure
+ Natural Cure makes it relatively immune to status
+ Grounded Poison typing makes it able to absorb TSpikes
+ Can and viably does run a very strong offensive LO set
+ Amazing special Defense and resistances to Water and Electric
+ Beats out most rapid spinners by scaring them out with offense
+ Usable as a lead or as a mid-game poke
+ High-average speed and amazing special attack
+ Variety and usage of different sets makes it not immediately predictable
+ Immune to Toxic
Cons:
- Very physically frail
- Unfortunate weaknesses to Fire and Ice limit its usability as a pure special wall
- Not fast enough to outspeed some threats that Froslass does
I could also compare it with things like Accelgor or Scolipede, but these are the three main spikers in the tier, and once again I think it's important that we focus on things that are commonly used.
From doing this, it basically helped me understand the true differences in spikers. What they all have in common is useful typing (ghost immunities and toxic spike absorbs/poison immunities), amazing abilities (Cursed Body, Intimidate, Natural Cure), and varying degrees of decent coverage and attack stats. The tradeoff from using Froslass over another spiker is mainly in bulk, predictability and utility, whereas you gain around 25-30 BP in speed. Whether or not it's really worth it to give something up early game in order to possibly take out a pokemon with DBond and lay a few spikes is a matter easily under contention, but I personally think that Froslass is equally if not less viable than other spikers in the tier and should be judged as such, and
no suspect of Froslass should take place.
P.S. It's possible that my semi-biased view may have clouded the accuracy of the Pros/Cons list. If I did leave any cons or pros out (and I did try and include them all), just tell me and I'll make note of them.