Im going through a similar time with my DD at the moment , she is 2.4 now . I'm still unsure if she has ASD, although our speech therapist hinted that might be the cause of her Social communication delay.
Between 14 and 18 months she started displaying few signs which were a bit quirky , lack of pointing, showing, occasional tippytoe walking, flapping when happy or excited and the odd spin ( all sometimes, not every day or often) - so I got a referral . Health Visitor said she's fine, but developmental paediatrician said she was a bit antisocial (Wasn't interested much in her just toys that were in the office).
Apart from the social thing, she is a happy little girl , affectionate, sleeps well, eats well, no routines, no tantrums, plays with variety of toys normally, imaginary play is ok not great , but she does like to have a little line up and organise stuff (not toys but weird stuff like my creams/body lotions :D, oranges, crayons, like identical things?)
Between 20-22 months she started pointing like crazy , and saying first words, stopped flapping, tiptoe walking and spinning.
Aged 2 she had about 40 words , right now at 2.4 she has bout 200 plus , also some short phrases like : Whats that, what happened, are you ok, Lets go, Ready steady go etc. She asks for things (but sometimes asks and hand leads which is also a potential ASD trait ?) , she points to show, follows point ok. Understands well. She's still behind on her speech id say 6 months but she's definitely getting better and not regressing. She can count to 10, and can sing some nursery rhymes (not all correctly but you can definitely guess the tune)
SALT says her IQ and cognitive skills are good but she's not very interested in people (more in objects) and lacks that social interaction and eye contact with strangers is poor.
Now at home she's really interactive with her family, grandparents, family members she knows, and she really likes seeing a little girl bit younger than her in or building.
She goes to nursery 2.5 hrs in the afternoon and likes it , enjoyed playgroups, parks .
But!
There are things that worry me.
She's not that bothered about kids, mostly does parallel play and is a bit crap at sharing toys (maybe its just a toddler thing) .
As much as she's good with familiar people she can absolutely blank strangers. Could she just be slow to warm up? God knows.
Im really torn and some days I think she's definitely on the spectrum, but there are periods when I think she's completely fine.
Anyhow, we'll continue with Salt, and Im looking into ABA tutor, but I dont think I will go for diagnosis before she's 3.5- 4, I kinda wanna see how she continues to develop.
Toys wise she likes building blocks, puzzles,sticker books, and lately little handbags where she can put a few of her bits and carry around :D